B What do scientists mean by 'Nothing'?

I very often hear scientists talking about how according to modern theories it's completely possible to something manifest out of nothing, and therefore there is nothing illogical of saying that universe came out of nothing. How is this 'nothing' defined and trough what logical process?

Very often i hear scientists explaining this 'something out of nothing' with an argument that in this 'nothing' particles pop out to existence spontaniously, some "branes" collide sometimes starting new universes, etc. But that is not 'nothing' to me. To me, 'nothing' means absolute nonexistence = no space, no random events, no branes, no nothing. Which is very problematic concept philosophically because just saying that "nonexistence is absolute" gives the nothingness a definition which questions it's nonexsistence. And, if nonexistence itself is nonexistent, then the opposite, the existence, must be true, and if nonexistence exists then it's again existent, and there is 'something' rather than 'nothing'.

Ofcourse that is just my own philosophy, but for certain a state where branes and random events do exist is not 'nothing', unless 'nothing' means just absence of matter. Is the 'nothing' just a name for a pre-state of the existence where anything we know did not yet exist, or does it mean a true 'nothingness'?

How is this pre-state, whatever it is, defined? I mean, how is it even theoretically possible to define it if we assume that nothing that we know didn't exist?

It would seem to me that you have been reading too much popular science and are interpreting it literally. Popular science has its role in encouraging people to think about science and to give a vague idea about what is going on. However, do not for one moment mistake popular science for science or think that you can learn actual science from reading it. Real scientific models are based on and described through mathematics as are the concepts within the models.

Also note that the A-level tag should only be used if you have an understanding of the subject at the level of a graduate student in physics or higher. It is clear from your question that this is not the case and I have relabelled the thread accordingly. Also note that this is a science forum and not a philosophy forum and that it is not a place for developing personal theories.

It would seem to me that you have been reading too much popular science and are interpreting it literally. Popular science has its role in encouraging people to think about science and to give a vague idea about what is going on. However, do not for one moment mistake popular science for science or think that you can learn actual science from reading it. Real scientific models are based on and described through mathematics as are the concepts within the models.

Also note that the A-level tag should only be used if you have an understanding of the subject at the level of a graduate student in physics or higher. It is clear from your question that this is not the case and I have relabelled the thread accordingly. Also note that this is a science forum and not a philosophy forum and that it is not a place for developing personal theories.

well yes, science panels and presentations by theoretical physicists mostly. i rarely watch any documentaries because they seem to be designed for people who have absolutely no idea even about the popular science.

but anyways, can you tell, what do they mean when they use term 'nothing' in this subject? even if it's not actually 'nothing', the term still is misleading and clearly refers to something that they have defined in some way. what it is, and how have scientists defined it - defined a state which, according to their own claims, is something in total absence of everything we know. Lacking even time, many seem to claim. or is it my misunderstanding that they would have been defined it in some way?

For example, a statement "In general relativity it's totally possible that universe came out of nothing", well, it sounds pretty much itself to my ear.

Staff: Mentor

For example, a statement "In general relativity it's totally possible that universe came out of nothing"

Where have you read or heard this statement? And if the answer is "in a pop science book or video", then the reply is that you shouldn't be trying to learn actual science from those sources. You need to look at textbooks or peer-reviewed papers.

Where have you read or heard this statement? And if the answer is "in a pop science book or video", then the reply is that you shouldn't be trying to learn actual science from those sources. You need to look at textbooks or peer-reviewed papers.

from 38:00 onwards, hear Ed's argument first and then how Seth replies to it.

"then the reply is that you shouldn't be trying to learn actual science from those sources." yes i totally understand this, and that's why i'm asking what does it actually mean in real science? i think you're not saying that the things they are talking in science panels etc. are just unscientific nonsense which shouldn't be listened at all, but that the things they are talking can be misleading because the words they use might not be accurately picked to describe the actual science, mostly done through mathematics. am i correct? so i think that the word 'nothing' and their statements in general actually holds scientific research behind them even though their public representations might be, or at least might feel a little bit of misleading.

i think you're not saying that the things they are talking in science panels etc. are just unscientific nonsense which shouldn't be listened at all, but that the things they are talking can be misleading because the words they use might not be accurately picked to describe the actual science, mostly done through mathematics. am i correct?

I'm saying I don't know, and without an acceptable source as a reference I'm not going to take the time to try to figure it out. It's work enough explaining what acceptable sources are saying. Trying to first figure out what, if any, actual science a non-acceptable source is referring to, and then explaining that, is way beyond the purpose or the resources of PF.